I was experimenting with the way gcc does register allocation depending on
different flags. I encountered one strange test file where adding a second asm
statement made a first one fail which did work before. Even stranger, when I
have both parts as separate functions before, the combined version compiles as
well. This interdependence between asm statements seems extremely
counterintuitive to me, and might cause difficult to find bugs in larger
projects.
The fact that omitting optimization causes my code to fail even for the version
including the single asm statements makes this bug seem related to bug 11203.
But the behaviour that some code does not compile even with optimizations, and
that adding some functions makes those parts compile as well, are strange
things not mentioned in that bug, so don't be hasty about marking this a
duplicate.
My compiler is a Gentoo build. I know you would love to make me reproduce this
with a plain vanilla compiler, but I beg you to simply compile my attached test
case with your version. If you can't reproduce the bug, I'll happily take this
to the gentoo bugzilla. But I expect the cause rather deep inside the sources,
nothing likely to be changed by some distribution patch set.
--
Summary: Interaction between different asm statements
Product: gcc
Version: 4.1.1
Status: UNCONFIRMED
Severity: normal
Priority: P3
Component: inline-asm
AssignedTo: unassigned at gcc dot gnu dot org
ReportedBy: Martin dot vGagern at gmx dot net
GCC build triplet: i686-pc-linux-gnu-gcc
GCC host triplet: i686-pc-linux-gnu-gcc
GCC target triplet: i686-pc-linux-gnu-gcc
http://gcc.gnu.org/bugzilla/show_bug.cgi?id=28635
